This invention relates to an electromagnetic wave detecting system which detects electromagnetic waves having specific wavelengths, and especially to an electomagnetic wave detecting camera system which is preferably suited to identify locations where hot electrons are generated and locations where resistive current leaks are generated.
For such type of prior art electromagnetic wave detecting system, there has been used an emission microscope or a microscope, which detect only electromagnetic waves having specific wavelengths.
In a case of detection using an infrared microscope, a semiconductor device as a device under test (DUT) is placed directly under the infrared microscope and as well a desired driving voltage is applied to the semiconductor device. Then, images of the semiconductor device at specified timings are taken by a high sensitive camera and recorded in a memory provided in a system controller, etc. By synthesizing such images, hot electron generating points and/or resistive current leaking points are identified.
In such analysis using the high sensitive camera, it is necessary to appropriately control open/close of a shutter of the camera at a specified timing during operation of the semiconductor device, and/or to control start and end of taking detected signals in the system.
With recent increase of the operating frequency of semiconductor devices, a strong demand exists for shortening detection time according to kinds of electromagnetic wave to be detected. However, since a shutter has a mechanical structure, its open/close operation does not follow its open/close control signal when a pulse width of the open/close control signal is narrowed. Therefore, there is a lower limit in the pulse widths of the shutter open/close control signal, and as a result, decreasing detection time under the limit is impossible to decrease the pulse width under the limit value. As a result, there is a problem that the detection time is hardly shortened.